Packaging containers, for use in connection with the housing, storing, shipping, and transportation of lengthy or elongated articles, such as, for example, glass or steel rods, pipes, lumber, vertical blinds, or the like, are often formed as structures having a substantially U-shaped cross-sectional configuration. Representative packaging containers of the aforenoted type are disclosed, for example, within U.S. Pat. No. 6,851,602 which issued to Gosis et al. on Feb. 8, 2005, U.S. Pat. No. 6,794,018 which issued to Clark on Sep. 21, 2004, U.S. Pat. No. 5,947,290 which issued to Loeschen on Sep. 7, 1999, U.S. Pat. No. 4,976,374 which issued to Macaluso on Dec. 11, 1990, and United States Patent Application Publication 2004/0185992 which was published in the name of Tisdale on Sep. 23, 2004. As can be readily appreciated from such prior art, a first type of packaging container comprises those packaging containers which are actually formed as a substantially rigid structure having the substantially U-shaped cross-sectional configuration, as exemplified by means of the structures disclosed within the aforenoted patents which issued to Gosis et al. and Macaluso, however, it is noted that due to the particular configuration of the packaging container, as well as the rigidity of the same, the a plurality of the packaging containers cannot effectively be disposed in a nested manner with respect to each other. Accordingly, when the packaging containers are being shipped from their site of manufacture to, for example, distributors or end users, or when the packaging containers are being stored within warehouse facilities of such distributors or end users, the packaging containers require a substantially large amount of space which is both wasteful and costly.
Ideally, then, a second type of packaging container of the aforenoted type is one in which the packaging container is initially fabricated as a substantially flat structure, and subsequently, oppositely disposed, laterally or transversely separated side portions of the substantially flat structure are subsequently folded upwardly, for example, so as to form the upwardly extending side wall members of the packaging container and which will cooperate with an intermediate portion of the substantially flat structure so as to thereby form the finalized U-shaped packaging container. This type of packaging container is exemplified by means of the packaging container structure disclosed within the aforenoted patent that issued to Clark, as well as the packaging container structure disclosed within the aforenoted patent publication that was published in the name of Tisdale. A common problem that usually develops, however, in connection with the fabrication of such a finalized U-shaped packaging container from the originally fabricated substantially flat structure, resides in the difficulty encountered in connection with the upward folding of the oppositely disposed, laterally or transversely separated side portions of the substantially flat structure so as to in fact form the upwardly extending side wall members of the packaging container. Accordingly, as can therefore be appreciated still further from the disclosures of the aforenoted patent to Clark, as well as from the aforenoted patent publication of Tisdale, the originally fabricated, substantially flat structures have means incorporated therewithin for facilitating the upward folding of the side wall members of the packaging containers such that the packaging containers can in fact achieve their substantially U-shaped cross-sectional configurations.
More particularly, as disclosed within FIGS. 1 and 2, which substantially correspond to FIGS. 2 and 3 of the aforenoted patent which issued to Clark, a packaging container is initially disclosed as being in its flattened state within FIG. 1. It is further seen that the structure of the flattened packaging container comprises a plurality of support members 28 having first and second sealing layers 30,34 respectively disposed upon the upper and lower surface portions thereof, and that in order to facilitate the upward folding of laterally or transversely spaced, oppositely disposed side wall members of the packaging container with respect to a central bottom wall member of the packaging container, a plurality of collapsible channels 24 are defined at predetermined locations within the flattened packaging container structure at which the laterally or transversely spaced, oppositely disposed side wall members of the packaging container are desired to be folded upwardly with respect to the central bottom wall member of the packaging container. In this manner, when each one of the laterally or transversely spaced, oppositely disposed side wall members of the packaging container is desired to be folded upwardly with respect to the central bottom wall member of the packaging container, a respective one of the collapsible channels 24 will in fact facilitate such upward folding of the particular one of the laterally or transversely spaced, oppositely disposed side wall members of the packaging container with respect to the central bottom wall member of the packaging container. It is noted, however, that in view of the incorporation or formation of the collapsible channels 24 within those regions of the flattened packaging container structure which will effectively become the corner regions of the subsequently formed U-shaped packaging container, the corner regions of the U-shaped packaging container are only effectively defined by means of the first and second sealing layers 30,34 which are respectively disposed upon the upper and lower surface portions of the packaging container structure. Accordingly, in view of the minimal number of plies 30,34 which therefore effectively comprise the corner regions of the packaging container, such corner regions of the packaging container will not exhibit substantial flexural beam strength which, of course, can be detrimental to the protective properties characteristic of the packaging container with respect to the articles contained therein.
Continuing further, and with reference now being made to FIG. 3, which substantially corresponds to FIG. 4A of the aforenoted patent publication to Tisdale, the packaging container is seen to comprise an upper or internal sheet member 10, and a lower or external sheet member 12, wherein each one of the upper or internal, and lower or external, sheet members 10,12 may comprise a multi-ply laminate or panel. The upper or internal sheet member 10 is adapted to be bonded to the upper or internal surface portion of the lower or external sheet member 12, however, prior to the bonding of the upper or internal sheet member 10 to the lower or external sheet member 12, the upper or internal sheet member 10 is severed into a plurality of sections 10a-10e as a result of the upper or internal sheet member 10 being slit along lines 17a-17d. In addition, when the various sections 10a-10e of the upper or internal sheet member 10 are bonded to the lower or external sheet member 12, the sections 10a-10e of the upper or internal sheet member 10 are spaced a predetermined distance apart from each other. In this manner, the spaces 17a-17d defined between the adjacent sections 10a-10e of the upper or internal sheet member 10 will facilitate the upward folding of the composite packaging container structure comprising the sections 10a-10e of the upper or internal sheet member 10 and the underlying lower or external sheet member 12.
It is to be appreciated, however, that this packaging container structure is somewhat similar to the packaging container structure which has been disclosed within the patent issued to Clark, as has been previously discussed, in that the corner structures of the packaging container of Tisdale will only be defined by means of the plies of the lower or external sheet member 12 and not, for example, by means of all of the plies comprising both the upper or internal sheet member 10 and the underlying lower or external sheet member 12 comprising the entire packaging container structure. Accordingly, still further, as was the case with the packaging structure of Clark, such corner regions of the packaging container will not exhibit substantial flexural beam strength which, again, can be detrimental to the protective properties characteristic of the packaging container with respect to the articles contained therein.
A need therefore exists in the art for a new and improved multi-ply packaging container, having a substantially U-shaped cross-sectional configuration comprising, for example, a bottom wall member and a pair of oppositely disposed upstanding side wall members integrally connected to the bottom wall member, wherein means could be incorporated within the corner regions of the packaging container, as defined between the bottom wall member and each one of the pair of oppositely disposed upstanding side wall members, so as to enable the packaging container to be initially fabricated in a flattened state, and yet facilitate the subsequent upward folding of the side wall members with respect to the bottom wall member, and wherein further, the number of plies comprising the packaging container is substantially the same throughout the bottom wall member, the pair of oppositely disposed upstanding side wall members, and within the corner regions of the packaging container, as defined between the bottom wall member and each one of the pair of oppositely disposed upstanding side wall members, so as to preserve the structural integrity and flexural beam strength properties of the packaging container.